Which of the following is true?

A: Every UNIX process gets its own virtual memory space, but threads can share their virtual memory.

B: Every user logged in to a Linux system has their own "virtual" view of the computer's memory, which by default allows them to share variables across different processes.

C: Processes running as regular users have their addresses in virtual memory, but processes running as root $($the administrator user$)$ use physical RAM addresses.

D: For security reasons, virtual memory addresses are required to be distinct across processes.